He-Man and the Masters of the Universe had done extremely well for Mattel. The one problem; the show was targeted towards the male species! Working closely with Filmation once again, Mattel created She-Ra, the twin-sister of He-Man. The action figure for girls was launched and initially everything went well.

Mattel once again asked Filmation to create sixty-five episodes of She-Ra Princess of Power. As before they wanted a simple cartoon that advertised their action figures and nothing more. As production on the He-Man and the Masters of the Universe series was halfway through season two, Filmation began animating She-Ra Princess of Power. The problem they faced was that according to the toy line She-Ra's greatest threat came from "jealous beauty" Catra. The Evil Horde from the Masters of the Universe action figure line had yet to be featured in the He-Man animated series, so a decision was made to have the Evil Horde as She-Ra's villains!

Filmation and Mattel planned something big to launch She-Ra Princess of Power, so they combined the first five episodes that had been animated, known collectively as "The Sword of She-Ra," and pieced them together renaming the film "The Secret of The Sword." It may not have broke box office records, but it was a good start for the She-Ra series. (Synopsis courtest of he-man.org)